Degradation Assembly

ABSTRACT

A degradation assembly comprises a rotating portion and a fixed portion. The rotating portion comprises a wear resistant tip bonded to a carbide bolster. The bolster is attached to a shaft adapted for a rotatable connection within a bore of the fixed portion. The fixed portion is adapted for a rigid connection to a driving mechanism. The fixed portion also comprises an o-ring slot formed within its bore and an o-ring being disposed within the bore. The o-ring is at least 15 percent compressed such that the o-ring resists rotation of the shaft.

CROSS REFERENCE IS RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 12/021,051 which is a continuation-in-part of U.S. patent application Ser. No. 12/021,019 which was a continuation in-part of U.S. patent application Ser. No. 11/971,965 which is a continuation of U.S. patent application Ser. No. 11/947,644, which was a continuation-in-part of U.S. patent application Ser. No. 11/844,586. U.S. patent application Ser. No. 11/844,586 is a continuation in-part of U.S. patent application Ser. No. 11/829,761. U.S. patent application Ser. No. 11/829,761 is a continuation in-part of U.S. patent application Ser. No. 11/773,271. U.S. patent application Ser. No. 11/773,271 is a continuation in-part of U.S. patent application Ser. No. 11/766,903. U.S. patent application Ser. No. 11/766,903 is a continuation of U.S. patent application Ser. No. 11/766,865. U.S. patent application Ser. No. 11/766,865 is a continuation in-part of U.S. patent application Ser. No. 11/742,304. U.S. patent application Ser. No. 11/742,304 is a continuation of U.S. patent application Ser. No. 11/742,261. U.S. patent application Ser. No. 11/742,261 is a continuation-in-part of U.S. patent application Ser. No. 11/464,008. U.S. patent application Ser. No. 11/464,008 is a continuation in-part of U.S. patent application Ser. No. 11/463,998. U.S. patent application Ser. No. 11/463,998 is a continuation-in-part of U.S. patent application Ser. No. 11/463,990. U.S. patent application Ser. No. 11/463,990 is a continuation-in-part of U.S. patent application Ser. No. 11/463,975. U.S. patent application Ser. No. 11/463,975 is a continuation in-part of U.S. patent application Ser. No. 11/463,962. U.S. patent application Ser. No. 11/463,962 is a continuation in-part of U.S. patent application Ser. No. 11/463,953. The present application is also a continuation-in-part of U.S. patent application Ser. No. 11/695672. U.S. patent application Ser. No. 11/695672 is a continuation in-part of U.S. patent application Ser. No. 11/686,831. All of these applications are herein incorporated by reference for all that they contain.

BACKGROUND OF THE INVENTION

Efficient degradation of materials is important to a variety of industries including the asphalt, mining, and excavation industries. In the asphalt industry, pavement may be degraded using attack tools, and in the mining industry, attack tools may be used to break minerals and rocks. Attack tools may also be used when excavating large amounts of hard materials. In asphalt recycling, often, a drum supporting an array of attack tools disposed within holders, together making up a degradation assembly, may be rotated and moved so that the attack tools engage a paved surface causing the tools and/or holders to wear. Much time is wasted in the asphalt recycling industry due to high wear of the degradation assemblies, which typically have a tungsten carbide tip.

U.S. Pat. No. 6,733,087 to Hall et al., which is herein incorporated by reference for all that it contains, discloses an attack tool for working natural and man-made materials that is made up of one or more segments, including a steel alloy base segment, an intermediate carbide wear protector segment, and a penetrator segment comprising a carbide substrate that is coated with a superhard material. The segments are joined at continuously curved interfacial surfaces that may be interrupted by grooves, ridges, protrusions, and posts. At least a portion of the curved surfaces vary from one another at about their apex in order to accommodate ease of manufacturing and to concentrate the bonding material in the region of greatest variance.

Examples of degradation assemblies from the prior art are disclosed in U.S. Pat. No. 6,824,225 to Stiffler, US Pub. No. 20050173966 to Mouthaan, U.S. Pat. No. 6,692,083 to Latham, U.S. Pat. No. 6,786,557 to Montgomery, Jr., US. Pub. No. 20030230926, U.S. Pat. No. 4,932,723 to Mills, US Pub. No. 20020175555 to Merceir, U.S. Pat. No. 6,854,810 to Montgomery, Jr., U.S. Pat. No. 6,851,758 to Beach, which are all herein incorporated by reference for all they contain.

BRIEF SUMMARY OF THE INVENTION

In one aspect of the present invention, a degradation assembly comprises a rotating portion and a fixed portion. The rotating portion comprises a wear resistant tip bonded to a carbide bolster. The bolster is attached to a shaft adapted for a rotatable connection within a bore of the fixed portion. The fixed portion is adapted for a rigid connection to a driving mechanism. The fixed portion also comprises an o-ring slot formed within its bore and an o-ring being disposed within the bore. The o-ring is at least 15 percent compressed such that the o-ring resists rotation of the shaft.

The shaft may be a shank or a sleeve. The shank may be disposed within a sleeve. The shaft may also be tapered on an end within the rotating surface to aid in reducing stress risers. The shaft may be formed from a steel body which is rigidly connected to the bolster. The rotating portion may comprise a tapered face adapted to be attached to the bolster. The bolster may also comprise a cavity with a lip adapted to attach to a locking mechanism. The fixed portion may comprise a wire snap ring slot formed within its bore. The o-ring may comprise a diameter smaller than a diameter of a wire snap ring. The bolster may comprise a tapered base end. The bolster may be mechanically attached to the sleeve by a locking mechanism. The locking mechanism may be axially disposed within the fixed portion, the rotating portion, and the shaft. The locking mechanism may be adapted to lock to a cavity of the bolster. The locking mechanism may be threaded through the fixed portion. A bore of the shaft may comprise a geometry of the locking mechanism. This may aid in supporting the locking mechanism and help in stabilizing it.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional diagram of an embodiment of an asphalt milling machine.

FIG. 2 is a cross-sectional diagram of an embodiment of a degradation assembly.

FIG. 3 is cross-sectional diagram of another embodiment of a degradation assembly.

FIG. 4 is cross-sectional diagram of another embodiment of a degradation assembly.

FIG. 5 is cross-sectional diagram of another embodiment of a degradation assembly.

FIG. 6 is cross-sectional diagram of another embodiment of a degradation assembly.

FIG. 7 is cross-sectional diagram of another embodiment of a degradation assembly.

FIG. 8 is cross-sectional diagram of another embodiment of a degradation assembly.

FIG. 9 is perspective diagram of another embodiment of a degradation assembly.

DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED EMBODIMENT

FIG. 1 is a cross sectional diagram of an embodiment of an asphalt milling machine 100. The asphalt milling machine 100 may comprise a driving mechanism 102 attached to a motor vehicle 103. A plurality of degradation assemblies 101 may be secured to the driving mechanism 102. The driving mechanism 102 may be a rotating drum, a chain, a rotor, or combinations thereof. The asphalt milling machine 100 may degrade a paved surface 104 of a road, sidewalk, or parking lot prior to applying new pavement. The driving mechanism 102 may rotate such that the degradation assemblies 101 engage the paved surface 104 as the motor vehicle 103 moves in a direction indicated by the arrow 105. In other embodiments of the invention, the driving mechanism 102 may be attached to a mining vehicle or other drilling machine.

FIG. 2 is a cross-sectional diagram of an embodiment of a degradation assembly 101. The degradation assembly 101 may comprise a rotating portion 201 and a wear resistant tip 202 bonded to a carbide bolster 203. The rotating portion 201 may aid in degradation of material. The rotating portion 201 may also be a sleeve. The bolster 203 may be attached to a shaft 204 adapted for a rotatable connection within a bore 209 of a fixed portion 205. The shaft 204 may be a shank or a sleeve. The bolster 203 may be isolated from the fixed portion 205. The fixed portion 205 may be adapted for a rigid connection to the driving mechanism. The fixed portion 205 may also comprise an o-ring slot 206 formed within its bore 209. An o-ring 207 may be at least 15 percent compressed such that the o-ring 206 resists rotation of the shaft 204. It is believed that an o-ring 207 resisting rotation of the shaft 204 will aid in wear resistance to the rotating portion 201 and to the degradation assembly 101. It is also believed that an o-ring 206 may prevent debris from entering the assembly 101. The o-ring 206 may be disposed on a first end 270 of the rotating portion 201. The fixed portion 205 may also comprise a wire snap ring slot 208 formed within its bore 209. This may stabilize the rotating portion 201 of the assembly 101. A snap ring 271 may be disposed around a second 210 end of the rotating portion 201. The assembly 101 may comprise a coaxial locking mechanism 211 adapted to attach to a cavity 212 of the bolster 203. The cavity 212 of the bolster 203 may comprise a lip 213 adapted to attach to a head 214 of the locking mechanism 211.

FIG. 3 is another cross-sectional diagram of an embodiment of a degradation assembly 101. The degradation assembly 101 may comprise a locking mechanism 211 adapted to attach to the bolster 203. The locking mechanism 211 may comprise a body 301 intermediate a head 214 and a base end 302. The head 214 may comprise a complementary geometry relative to a geometry of the cavity 212 of the bolster 203. The cavity 212 may comprise multiple 0-rings 206 that may aid in wear resistance. The body 301 may be threadedly attached to the base end 302. The base end 302 may comprise a spring 303. The spring 303 may add to the life of the assembly 101. The base end 302 may also comprise a snap ring 271 and be disposed around a threaded attachment 350 adapted to connect the rotating portion 201 and the fixed portion 205 of the degradation assembly 101. The base end 302 may also be threadedly attached to the shaft 204 of the assembly 101. The degradation assembly 101 may comprise a fluid passage 304 within the fixed portion 205. The fluid passage 304 may run through the shaft 204 and into surrounding portions of the degradation assembly 101. A fluid may pass through the base 302 and into the degradation assembly 101 for added wear resistance and lubrication.

FIG. 4 is another cross-sectional diagram of an embodiment of a degradation assembly 101. The fixed portion 205 of the degradation assembly 101 may comprise a snap ring 271 disposed at the second end 210 of the rotating portion 201 adapted to secure the rotating portion 201 to the fixed portion 205. The rotating portion 201 may rotate around the snap ring 271. A plurality of springs 303 may be disposed around the second end 210 of the rotating portion 201 as well. It is believed that the spring 303 may minimize axial wobble in the degradation assembly. A second spring 402 may be a retaining spring. The second spring 402 may stabilize the rotating portion 201.

FIG. 5 is another cross-sectional diagram of an embodiment of a degradation assembly 101. The fixed portion 205 of the degradation assembly 101 may comprise a threadform 550 adapted to be threadedly attached to a holder 501. A first end 502 of the fixed portion 205 may comprise a hexagonal geometry. The fixed portion 205 may comprise a diameter less than a diameter of the rotating portion 201.

FIG. 6 is another cross-sectional diagram of an embodiment of a degradation assembly 101. The degradation assembly 101 may comprise a carbide bolster 203 intermediate a tip 202 and a rotating portion 201. The rotating portion 201 may comprise a taper 600 adapted to receive a taper 601 of the carbide bolster 203. The tapers may aid in wear resistance to the assembly during degradation of a material. The taper 601 may be able to withstand greater forces at more angles than if there were no taper. The bolster 203 may be brazed 602 along its taper to the rotating portion 201. In some embodiments, the bolster is only brazed along the taper.

FIG. 7 is another cross-sectional diagram of an embodiment of a degradation assembly 101. The degradation assembly 101 may comprise a carbide bolster 203 intermediate a tip 202 and a rotating portion 201. The rotating portion 201 may comprise a taper 600 adapted to receive a taper 601 of the carbide bolster 203. The bolster 203 may be brazed 602 along a base portion 700 to a face 701 of the rotating portion. This may provide the advantage of minimizing the surface areas that are brazed since the applicants have found that a larger surface area compromising the integrity of the braze. FIG. 8 show the bolster 800 may be brazed to a steel body along a taper of the base of the bolster. A cavity in the bolster reduces the surface area of the braze. In some embodiments, voids may be formed along the taper to reduce surface area of the braze.

FIG. 9 discloses a degradation assembly 101 with flats 900 incorporated on the rotating portion 201. These flats may be use to apply torque to the rotating portion with a tool such as a wrench. In some embodiments, the degradation assembly is used for a period of time and then manually rotated so that wear occurs more evenly. Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention. 

1. A degradation assembly comprising: a rotating portion and a fixed portion; the rotating portion comprising a wear resistant tip bonded to a carbide bolster, the bolster being attached to a shaft adapted for rotatable connection within a bore of the fixed portion; the fixed portion being adapted for rigid connection to a driving mechanism; and the fixed portion comprising a mechanism adapted to substantially resist the rotation of the shaft
 2. The assembly of claim 1, wherein the mechanism comprises an o-ring slot formed within in the bore and an o-ring being disposed within it, the o-ring being at least 15 percent compressed such that the o-ring substantially resists rotation of the shaft.
 3. The assembly of claim 1, wherein the shaft is a shank or a sleeve.
 4. The assembly of claim 3, wherein the shank is a disposed within a sleeve.
 5. The assembly of claim 1, wherein the shaft is tapered on an end within the rotating portion.
 6. The assembly of claim 1, wherein the shaft is formed from a steel body which is rigidly connected to the bolster.
 7. The assembly of claim 1, wherein the bolster comprises a tapered base end.
 8. The assembly of claim 1, wherein the bolster is isolated from the fixed portion.
 9. The assembly of claim 1, wherein the bolster comprises a cavity formed within its base and comprising an internal lip adapted to attach a locking mechanism.
 10. The assembly of claim 1, wherein the bolster comprises a diameter less than a diameter of the fixed portion.
 11. The assembly of claim 1, wherein the bolster is mechanically attached to the sleeve by a locking mechanism.
 12. The assembly of claim 11, wherein the locking mechanism is axially disposed within the fixed portion, the rotating portion, and the shaft.
 13. The assembly of claim 11, wherein the locking mechanism is adapted to interlock with a cavity of the bolster.
 14. The assembly of claim 11, wherein the locking mechanism comprises a threadform.
 15. The assembly of claim 11, wherein the locking mechanism comprises a geometry formed by an interlocking end of the shaft.
 16. The assembly of claim 1, wherein the rotating portion comprises a tapered face adapted to abut to the bolster.
 17. The assembly of claim 1, wherein the sleeve comprises a first end with a diameter greater than a diameter of a first end of the fixed portion.
 18. The assembly of claim 1, wherein the mechanism comprises a pressurized surface adapted to abut the rotating portion.
 19. The assembly of claim 1, wherein the tip comprises a diamond layer bonded to a substrate and wherein the substrate comprises an axial thickness less than the axial thickness of the diamond. 